Mourinho's men have been charged with "failing to control their players" by the Football Association following Monday's FA Cup quarter-final tie.
The FA has referred to the incident in the 35th minute, which saw United players gather around the referee after Ander Herrera's red card.
The statement by the Football Association went on to say:"The club have until 6pm on Friday 17 March 2017 to respond to the charge."
Following Monday's @EmiratesFACup tie at @ChelseaFC, @ManUtd have been charged for failing to control their players: https://t.co/LeW3WFEN8p
— The FA (@FA) 14 de marzo de 2017